CLYDESDALE Bank is being sued by property developers who say they were charged fees of more than £400,000 for an overdraft they could not use.

One of the largest banks in the country, Clydesdale granted the £2.5 million overdraft in 2007 to Andy and Moira Pearson who run award-winning Tweed Homes. Their intention was to finance the building of new homes on land bought from the Duke of Roxburghe in the Borders.

The couple claim they were refused further access to the money without explanation, after using about half of the fund. They say that over the following seven years they endured "anguish, anxiety and stress", and say they were powerless to prevent massive charges which appeared on statements as arrangement fees, exit fees and security fees.

They also claim that on top of the fees, totalling more than one third of the sum of money they borrowed, interest accrued. It is believed that if the claims are correct, it could be one of the most expensive overdraft facilities granted by a high street bank.

Last week, lawyers acting for the Pearsons lodged a legal action against Clydesdale Bank in Edinburgh's Court of Session, claiming the bank breached its contract with them and they are seeking £2.3m in damages. The papers say the bank notified the couple last year that it was no longer prepared to provide financial support.

"Tweed Homes has been trying to settle matters amicably with Clydesdale for some time," said Andy Pearson, former chairman of industry body Homes for Scotland.

""Our case has been passed from pillar to post for too long. We have finally lost patience with the bank and now find it necessary to try to achieve satisfaction through the courts."

Meanwhile, a group of businesses that claim to have been pushed to the brink of collapse by Royal Bank of Scotland's controversial Global Restructuring Group (GRG) has moved a step closer to seeing directors of the unit in court.

The RBS-GRG business action group secured financial backing from US litigation funders to pursue a £600m claim against the bank. It plans to launch an "unlawful means conspiracy action" case against the bank and four of its executives who held senior posts at the time of the alleged wrongdoing.

About 270 small and medium-sized firms, one-third of them in Scotland, claim GRG, which was supposed to help struggling businesses, deliberately forced companies to the wall to grab their assets on the cheap. It is claimed GRG forced distressed small firms into bankruptcy to improve RBS's capital position.